Electrical connection plug for multipolar lead of active implantable medical device

A process for manufacturing an electrical connection plug for multipolar lead of an active implantable medical device, the method comprising:

• providing an axial pin having a free end forming an axial electrical contact, a mounting rod adapted to connect with an inner central conductor, and a flange extending radially from the axial pin between the free end and the mounting rod;
• inserting the axial pin through a cylindrical bore in a retaining sleeve such that an end face of the retaining sleeve abuts a flange extending radially from the axial pin;
• inserting the axial pin through a locking ring which abuts a second face of the retaining sleeve;
• forming a plug body having a central bore, the central bore defining an inner circumference;
• securing the retaining sleeve to an inner circumference of the plug body such that the retaining sleeve is secured axially to the plug body and the axial pin is allowed to rotate relative to the plug body and the retaining sleeve;
• wherein the inner central conductor is coated with a lubricant to reduce rotational friction and facilitate rotation of the central conductor within the central bore.

An electrical connection plug for multipolar lead of an active implantable medical device, comprising:

• a cylindrical outer surface having a plurality of axially distributed annular contacts, and carrying at one free end an axial contact;
• an axial pin end of conductive material comprising an axial contact at one end and a mounting rod at a second end, the mounting rod connected to an inner central conductor of the lead;
• a plug body of insulating material, comprising a central bore housing the central conductor and the pin rod and carrying at its outer surface the annular contacts, the plug body also housing of the connection conductors to the respective annular contacts, and
• a connection device between the pin and the plug body, forming a connection interface between the pin rod and the inner wall of the bore of the plug body in the vicinity of its outlet, wherein the connection device of the pin to the plug body comprises:
• (a) a retaining sleeve mounted on the pin rod so that:
• axially, the end face of this sleeve abuts against a collar formed on the rod, and radially, the outer surface of the sleeve comes into direct contact with the inner wall of the bore of the plug body at the outlet thereof;
• (b) a locking ring, secured to the pin rod so that, axially, the retaining sleeve is clamped between the collar of the rod and the locking ring, if necessary leaving a degree of freedom in rotation between the plug and the pin, and
• (c) means for directly securing the sleeve to the plug body at the point of its contact with the inner wall of the bore;
• wherein the central conductor is coated with a lubricant to reduce rotational friction and facilitate rotation of the central conductor within the central bore.